For the freely rotatable mounting of a drum-like mold for the production of plastic pipes by the centrifugal molding process, large bearing means are required which should be as quiet as possible for environmental protection reasons and must be splash-proof so that the matrix can be heated and cooled with water from the outside. Bearings of this type are unknown to date so that the bearing according to the present invention makes it possible to satisfy the need which has existed up to the present.